FRITZ!Box 7340 – Service - Knowledge Base

Setting up automatic port sharing via UPnP

By default, the FRITZ!Box's firewall blocks all incoming connections from the internet. If you enable the FRITZ!Box's UPnP function, then internet applications (for example chat software, online games, file-sharing software) can automatically adjust the FRITZ!Box's security settings and set up the necessary port sharing settings by themselves.

Requirements / Restrictions

Important:The FRITZ!Box is not accessible from the internet over IPv4 when used on a DS-Lite internet connection. When DS-Lite is active, the status "IPv4 over DS Lite" is displayed under "Connections" on the "Overview" page of the FRITZ!Box user interface.

1 Configuring the FRITZ!Box for automatic port sharing

Enable the option "Transmit status information over UPnP". If the option is not displayed, enable the Advanced View first.

Click "Apply" to save the settings.

Click "Internet" and then "Permit Access".

Click on the "Port Sharing" or "Port Forwarding" tab.

Enable the option "Allow changes to security settings over UPnP".

Click "Apply" to save the settings.

2 Configuring an application to use UPnP

Configure the application so that it uses UPnP. Refer to the manufacturer for information on how to set it up, for example consult the manual.

3 Configuring the computer's firewall

If the application is installed on a computer with its own firewall (for example Windows firewall), you must also configure the firewall:

Important:If changing the security settings via UPnP is allowed, malicious software can also cause ports to be shared, thus bypassing the FRITZ!Box's firewall. You should therefore set up a firewall on all computers in the home network for security reasons.

Configure the computer's firewall according to the manufacturer's instructions so that the server service or application can be accessed from the FRITZ!Box home network.

Now UPnP-capable applications automatically open the required ports in the FRITZ!Box.

You can find a current overview of ports automatically enabled for port sharing in the FRITZ!Box user interface under "internet > Permit Access > Port Sharing" in the "Ports Opened via UPnP" section. You can click the (Delete) button to manually close individual ports.